UPDATED: Under FDA investigation, Bayer releases new data on Essure contraceptive with a positive twist

Under investigation by the FDA following claims of dangerous side effects and fraudulent clinical trial data, Bayer has released new data from a long-term study the German drugmaker says supports the safety and effectiveness of its Essure contraceptive inserts.

The 5-year follow-up study tracked the initial group of women in the Phase III clinical trial that led to the 2002 FDA approval of Essure. During the study, pelvic pain was reported in no more than 7% of study participants at any visit, the company said in a press release. Women with pre-existing chronic pain were excluded from participation and no study participants reported persistent pelvic pain of any kind at the three-, four-, and 5-year follow-up visits.

Essure is placed hysteroscopically and blocks the fallopian tubes to achieve permanent birth control. The 5-year study evaluating long-term effectiveness of the device was required by the FDA as part of the evaluation and approval of Essure.

"The results of this study, which are consistent with other published literature on Essure, document the extended 5-year effectiveness, safety, and tolerability of Essure inserts," Dr. John Nichols Jr., a study investigator, said in a statement.

Still, an article published by The New York Times on Sunday cited results from a long-term trial published last week in the Journal of Minimally Invasive Gynecology. In that study, the newspaper said, only 366 of an original 518 participants were followed for the full 5 years.

Of those women who were tracked for the full time frame of the study, 15 had hysterectomies, of which two of the procedures might "possibly" be related to Essure. Thirty-eight percent of the same group of women experienced unusually heavy periods on a recurring basis. One in 20 patients had recurrent pelvic pain, and one in 15 had recurrent painful periods.

Early last month, the FDA announced it would investigate the Essure birth control device, following complaints of fraud during the clinical trial and claims of dangerous side effects. According to a petition filed with the regulatory agency on behalf of hundreds of women, the device caused adverse events like device migration and organ perforation.

Bayer purchased the device through its $1.1 billion acquisition of Conceptus in 2013.

- read the Bayer release 
- see the NYT's article

Editor's note: This story has been updated to include information about the study cited by The New York Times.

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